Night vision apparatus or devices, such as night vision binoculars, goggles, monoculars and scopes, enable users to have improved vision in low light or no light conditions, for example, in military, surveillance, law enforcement, hunting and rescue applications. Night vision apparatus typically comprise an image intensifier tube and associated circuitry for capturing photons which are converted to electrons, amplified and converted back to photons to produce an enhanced image of the scene being viewed through the apparatus. Such devices are typically hand-held, head-mounted, helmet-mounted or mounted to equipment, such as a weapon.
Developments in the design of night vision apparatus over seven decades include improvements in light amplification, image resolution and contrast, signal to noise ratios and reliability, a reduction in power consumption, size and weight of the apparatus and the inclusion of features such as auto-gating to protect users against temporary blindness. Further improvements in the design of night vision apparatus continue to be sought.
One feature of night vision apparatus is that they have a limited useful lifetime due to degradation of the image intensifier tube through activation and use of the image intensifier tube. Degradation of the image intensifier tube can lead to a reduction in the amplification of light levels and a degradation in the image displayed to the user, such as the representation of distances inaccurately. Whilst certain levels of degradation can be tolerated depending on the application for which the night vision apparatus are being used, beyond certain levels of degradation, the night vision apparatus must not be used, for example in aviation and other critical applications.
Consequently, it is important that night vision apparatus are maintained and their performance monitored to ensure the apparatus are in working order and replaced when necessary. Such maintenance is typically performed by taking the apparatus apart and inspecting the components and recording and tracking relevant information on a spreadsheet or the like. In many countries certain restrictions apply to night vision apparatus and it is a requirement to also record certain data relating to the night vision apparatus, such as serial numbers and types of apparatus. These maintenance and recordal obligations can be very time consuming and laborious particularly where a fleet of night vision apparatus is maintained, such as in military and law enforcement organisations.